Single cam double bow knotter for baler

Abstract

A knotter assembly for a baler allows for two bow knots to be formed per knotter tie cycle using a single drive cam gear and two bill hooks while maintaining needle penetration requirements. The knotter assembly includes a first twine disc driven by a first twine disc drive gear and a second twine disc driven by a second twine disc drive gear. The knotter assembly includes a first bill hook driven by a first bill hook drive gear and a second bill hook driven by a second bill hook drive gear. The knotter assembly also includes a cam gear driving the bill hook drive gears and the twine disc drive gears and a main knotter drive shaft driving the cam gear. A needle is located adjacent the twine discs.

The invention claimed is: 
     
       1. A baler having a knotter assembly configured to take strands of binding material looped around a finished bale and binding the strands with two knots per knotter tie cycle, the knotter assembly comprising:
 a first twine disc driven by a first twine disc drive gear; 
 a second twine disc driven by a second twine disc drive gear; 
 a first bill hook driven by a first bill hook drive gear; 
 a second bill hook driven by a second bill hook drive gear; 
 a cam gear driving the bill hook drive gears and the twine disc drive gears; 
 a main knotter drive shaft driving the cam gear; and 
 a needle is located adjacent the twine discs. 
 
     
     
       2. The baler of  claim 1  wherein the bill hooks are positioned axial to the main knotter drive shaft and transversely to the operating direction of the baler. 
     
     
       3. A method of forming two knots in strands of binding material around a finished bale per knotter tie cycle in a baler with a knotter assembly, the knotter assembly having a first twine disc driven by a first twine disc drive gear, a second twine disc driven by a second twine disc drive gear, a first bill hook driven by a first bill hook drive gear, a second bill hook driven by a second bill hook drive gear, a cam gear driving the bill hook drive gears and the twine disc drive gears, a main knotter drive shaft driving the cam gear, and a needle located adjacent the twine discs, the method comprising:
 using the needle to place upper and lower twines across a valley created between first and second twine discs; 
 rotating the first twine disc to grab the upper and lower twines to move the upper and lower twines into a first tensioner positioned over the first bill hook on a side of the knotter assembly to begin the knot formation; 
 retracting the needle to place the upper and lower twines across the valley again; 
 rotating the second twine disc in an opposite direction of the first twine disc to grab the upper and lower twines and pull them into a second tensioner positioned in front of the second bill hook; 
 rotating the two bill hooks around the twines being held by their respective disc and tensioner; 
 pulling the tails of the twine out of the tensioners as the bill hooks finish their rotation; and 
 pulling the knots off of the bill hooks by rearward motion of the bale.